A 5-Phase Fault-Tolerant Brushless Permanent Magnet Motor Drive for an Aircraft Thin Wing Surface Actuator

This paper describes work on an integrated Electro Hydrostatic Actuator (EHA) intended as a technology demonstrator to satisfy future aircraft requirements for smaller profile wing surfaces. The design and analysis of an integrated actuator package, comprising a high speed, 5-phase, brushless permanent magnet (PM) machine driving a variable displacement hydraulic pump is considered. The main goals of the design are a high level of actuator integration in order to minimize weight and volume, fault tolerance and high reliability. The constraints imposed by the operating environment, the converter supply and the hydraulic fluid on the machine deign will be addressed.